public static MethodCallExpression GetMethodCallExpression_Like <TSource, TCondition>(
IQueryable <TSource> sourceDB
, PageQueryParam <TCondition> QueryParam
, PropertyInfo[] TSourceDBProp
, PropertyInfo QueryTypeMemberInfo
, QueryParamAttribute QueryParamAttr
, PropertyInfo TSourceProp
, object QueryParamFieldValue
, ParameterExpression FunParam
)
{
MethodCallExpression mainExpression = null;
MemberExpression LeftProp = Expression.Property(FunParam, TSourceProp.Name);
//System.Linq.Expressions.ParameterExpression RightProp = Expression.Parameter(QueryMemberInfo.ReflectedType);
ConstantExpression RightProp = Expression.Constant(QueryParamFieldValue);
mainExpression = Expression.Call(LeftProp,
TSourceProp.PropertyType.GetMethod("Contains", new Type[] { QueryTypeMemberInfo.PropertyType }),
RightProp);
return(mainExpression);
}
public static MethodCallExpression GetMethodCallExpression_LikeStart <TSource, TCondition>(
IQueryable <TSource> sourceDB
, PageQueryParam <TCondition> QueryParam
, PropertyInfo[] TSourceDBProp
, PropertyInfo QueryTypeMemberInfo
, QueryParamAttribute QueryParamAttr
, PropertyInfo TSourceProp
, object QueryParamFieldValue
, ParameterExpression FunParam
)
{
MethodCallExpression mainExpression = null;
MemberExpression LeftProp = Expression.Property(FunParam, TSourceProp.Name);
var itemParameter = Expression.Parameter(typeof(TSource), "item");
var functions = Expression.Property(null, typeof(EF).GetProperty(nameof(EF.Functions)));
var like = typeof(DbFunctionsExtensions).GetMethod(nameof(DbFunctionsExtensions.Like), new Type[] { functions.Type, TSourceProp.PropertyType, QueryTypeMemberInfo.PropertyType });
mainExpression = Expression.Call(
null,
like,
functions,
LeftProp,
Expression.Constant(QueryParamFieldValue));
return(mainExpression);
}
public static BinaryExpression GetBinaryExpression <TSource, TCondition>(
IQueryable <TSource> sourceDB
, PageQueryParam <TCondition> QueryParam
, PropertyInfo[] TSourceDBProp
, MemberInfo QueryTypeMemberInfo
, QueryParamAttribute QueryParamAttr
, PropertyInfo TSourceProp
, object QueryParamFieldValue
, ParameterExpression FunParam
)
{
BinaryExpression mainExpression = null;
MemberExpression LeftProp = Expression.Property(FunParam, TSourceProp.Name);
//System.Linq.Expressions.ParameterExpression RightProp = Expression.Parameter(QueryMemberInfo.ReflectedType);
ConstantExpression RightProp = Expression.Constant(QueryParamFieldValue);
switch (QueryParamAttr.OperatorType)
{
case OperatorType.Equal:
mainExpression = Expression.MakeBinary(ExpressionType.Equal, LeftProp, RightProp);
break;
case OperatorType.NotEqual:
mainExpression = Expression.MakeBinary(ExpressionType.NotEqual, LeftProp, RightProp);
break;
case OperatorType.GreaterThan:
mainExpression = Expression.MakeBinary(ExpressionType.GreaterThan, LeftProp, RightProp);
break;
case OperatorType.GreaterThanOrEqual:
mainExpression = Expression.MakeBinary(ExpressionType.GreaterThanOrEqual, LeftProp, RightProp);
break;
case OperatorType.LessThan:
mainExpression = Expression.MakeBinary(ExpressionType.LessThan, LeftProp, RightProp);
break;
case OperatorType.LessThanOrEqual:
mainExpression = Expression.MakeBinary(ExpressionType.LessThanOrEqual, LeftProp, RightProp);
break;
default:
break;
}
return(mainExpression);
}
public static Expression GetMethodCallExpression_NotIn <TSource, TCondition>(
IQueryable <TSource> sourceDB
, PageQueryParam <TCondition> QueryParam
, PropertyInfo[] TSourceDBProp
, PropertyInfo QueryTypeMemberInfo
, QueryParamAttribute QueryParamAttr
, PropertyInfo TSourceProp
, object QueryParamFieldValue
, ParameterExpression FunParam
)
{
//var Fun = typeof(Enumerable).GetMethod("Contains", new Type[] { typeof(IEnumerable<int>), typeof(int) });
Expression mainExpression = null;
MemberExpression LeftProp = Expression.Property(FunParam, TSourceProp.Name);
var itemParameter = Expression.Parameter(typeof(TSource), "item");
var functions = Expression.Property(null, typeof(EF).GetProperty(nameof(EF.Functions)));
//var like = typeof(Enumerable).GetMethod("Contains", new Type[] { functions.Type, TSourceProp.PropertyType, QueryTypeMemberInfo.PropertyType });
var FunGeneric = typeof(Enumerable).GetMethods().First(o => o.Name == "Contains" && o.GetParameters().Length == 2);
var Fun = FunGeneric.MakeGenericMethod(TSourceProp.PropertyType);
mainExpression = Expression.Call(
null,
Fun,
Expression.Constant(QueryParamFieldValue),
LeftProp);
mainExpression = Expression.Not(mainExpression);
return(mainExpression);
}
private static IQueryable <TSource> GetWhere <TSource, TCondition>(
IQueryable <TSource> sourceDB
, PageQueryParam <TCondition> QueryParam
, PropertyInfo[] TSourceDBProp
, PropertyInfo QueryTypePropertyInfo
)
{
////查询条件特性
QueryParamAttribute QueryParamAttr = null;
#region 参数是否满足条件判断
if (TSourceDBProp == null)
{
return(sourceDB);
}
if (QueryTypePropertyInfo == null)
{
return(sourceDB);
}
QueryParamAttr = QueryTypePropertyInfo.GetCustomAttribute <QueryParamAttribute>();
if (QueryParamAttr == null)
{
return(sourceDB);
}
if (QueryParamAttr.FieldName == null)
{
return(sourceDB);
}
#endregion
//// 作用的条件对象属性
var TSourceProp = TSourceDBProp.First(o => o.Name == QueryParamAttr.FieldName);
if (TSourceProp == null)
{
return(sourceDB);
}
var QueryParamFieldValue = QueryTypePropertyInfo.GetValue(QueryParam.Condition);
if (QueryTypePropertyInfo.PropertyType.IsDefaultValue(QueryParamFieldValue))
{
return(sourceDB);
}
Expression mainExpression = null;
ParameterExpression FunParam = Expression.Parameter(typeof(TSource));
switch (QueryParamAttr.OperatorType)
{
case OperatorType.Equal:
case OperatorType.NotEqual:
case OperatorType.GreaterThan:
case OperatorType.GreaterThanOrEqual:
case OperatorType.LessThan:
case OperatorType.LessThanOrEqual:
mainExpression = GetBinaryExpression(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, QueryParamFieldValue
, FunParam
);
break;
case OperatorType.Like:
mainExpression = GetMethodCallExpression_Like(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, QueryParamFieldValue
, FunParam
);
break;
case OperatorType.StartWith:
mainExpression = GetMethodCallExpression_LikeStart(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, QueryParamFieldValue.ToString() + "%"
, FunParam
);
break;
case OperatorType.EndWith:
mainExpression = GetMethodCallExpression_LikeStart(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, "%" + QueryParamFieldValue.ToString()
, FunParam
);
break;
case OperatorType.In:
mainExpression = GetMethodCallExpression_In(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, QueryParamFieldValue
, FunParam
);
break;
case OperatorType.NotIn:
mainExpression = GetMethodCallExpression_NotIn(sourceDB
, QueryParam, TSourceDBProp
, QueryTypePropertyInfo, QueryParamAttr
, TSourceProp, QueryParamFieldValue
, FunParam
);
break;
default:
break;
}
if (mainExpression == null)
{
return(sourceDB);
}
//System.Linq.Expressions.ConstantExpression ModelValue = Expression.Constant(QueryMemberInfo.GetMemberValue(QueryParam)) ;
Expression <Func <TSource, bool> > whereExpression = Expression.Lambda <Func <TSource, bool> >(mainExpression, FunParam);
sourceDB = sourceDB.Where(whereExpression);
return(sourceDB);
}
